View source for Biology:Leviviridae

[[File:Ms2capsid surface.png|thumb|Cartoon representation of the entire bacteriophage MS2 protein capsid (pdb id 1AQ3).]]
{{Virusbox
| taxon              = Leviviridae
| subdivision_ranks  = Genera
| subdivision        =
* ''[[Biology:Allolevivirus|Allolevivirus]]''
* ''[[Biology:Levivirus|Levivirus]]''
}}

'''''Leviviridae''''' is a family of viruses. Bacteria, including Enterobacteria, [[Biology:Caulobacter|Caulobacter]], [[Biology:Pseudomonas|Pseudomonas]], and [[Biology:Acinetobacter|Acinetobacter]] serve as natural hosts for these [[Biology:Bacteriophage|bacteriophage]]s. There are currently four species in this family, divided among 2 genera.<ref name=ViralZone>{{cite web|title=Viral Zone|url=http://viralzone.expasy.org/all_by_species/163.html|publisher=ExPASy|accessdate=15 June 2015}}</ref><ref name=ICTV>{{cite web|last1=ICTV|title=Virus Taxonomy: 2014 Release|url=http://ictvonline.org/virusTaxonomy.asp|accessdate=15 June 2015}}</ref> They are small RNA viruses with linear, positive-sense, single-stranded RNA genomes that encode only four proteins. All phages of this family require bacterial pili to attach to and infect cells.<ref name=Bollback2001>{{cite journal|last1=Bollback|first1=JP|last2=Huelsenbeck|first2=JP|title=Phylogeny, genome evolution, and host specificity of single-stranded RNA bacteriophage (family Leviviridae).|journal=Journal of Molecular Evolution|date=February 2001|volume=52|issue=2|pages=117–28|pmid=11231891|doi=10.1007/s002390010140|bibcode=2001JMolE..52..117B}}</ref>

==Taxonomy==
The family has two genera, both of which currently have two known species.

<big>'''Group: ssRNA(+)'''</big>
{{Collapsible list|title= <big>Order: Levivirales</big>
|1={{Collapsible list| framestyle=border:none; padding:1.0em;|title=Family: Leviviridae
|1={{hidden begin|title=<small>Genus: [[Biology:Allolevivirus|Allolevivirus]]</small>}}
*<small>Escherichia virus FI</small>
*<small>'''''[[Biology:Escherichia virus Qbeta|Escherichia virus Qbeta]]'''''</small>
{{hidden end}}
|2={{hidden begin|title=<small>Genus: [[Biology:Levivirus|Levivirus]]</small>}}
*<small>Escherichia virus BZ13</small>
*<small>'''''[[Biology:Escherichia virus MS2|Escherichia virus MS2]]'''''</small>
{{hidden end}}
}}
}}<ref name=ICTV />

==Structure==
Viruses in Leviviridae are non-enveloped, with icosahedral and  Spherical geometries, and T=3 symmetry. The diameter is around 26&nbsp;nm. Genomes are linear and non-segmented, around 4kb in length. The genome codes for 4 proteins.<ref name=ViralZone />

{| class="wikitable sortable" style="text-align:center"
|-
! Genus !! Structure || Symmetry !! Capsid !! Genomic arrangement !! Genomic segmentation
|-
|Levivirus||Icosahedral||T=3||Non-enveloped||Linear||Monopartite
|-
|Allolevivirus||Icosahedral||T=3||Non-enveloped||Linear||Monopartite
|}

==Life cycle==
Entry into the host cell is achieved by adsorption into the host cell. Replication follows the positive stranded RNA virus replication model. Positive stranded RNA virus transcription is the method of transcription. Translation takes place by suppression of termination. The virus exits the host cell by bacteria lysis.
Enterobacteria, caulobacter, pseudomonas, and  acinetobacter serve as the natural host.<ref name=ViralZone />

{| class="wikitable sortable" style="text-align:center"
|-
! Genus !! Host details !! Tissue tropism !! Entry details !! Release details !! Replication site !! Assembly site !! Transmission
|-
|Levivirus||Enterobacteria||None||Pili||Lysis||Cytoplasm||Cytoplasm||Contact
|-
|Allolevivirus||Enterobacteria||None||Pili||Lysis||Cytoplasm||Cytoplasm||Contact
|}

==Genome==
The four proteins encoded are the coat, replicase, maturation and lysis proteins.<ref name=Bollback2001 />

==References==
{{Reflist}}

==External links==
* [http://viralzone.expasy.org/all_by_species/163.html '''Viralzone''': Leviviridae]
* [http://ictvonline.org/virusTaxonomy.asp '''ICTV''']
{{Baltimore classification}}

{{Taxonbar|from=Q3772918}}

[[Category:Leviviridae| ]]
[[Category:Virus families]]
[[Category:Riboviria]]

{{Sourceattribution|Leviviridae|1}}